frasenci

As an experiment, perhaps set the float voltage to be 29.0 V (same as the absorb/bulk voltage). That will tell you whether the charger is capable of 29.0 V, and it will give your battery a much-needed full charge. Watch the charge current carefully (don't leave it unattended like this); when the net charge current into the battery reaches about C/20, change the float voltage setting back to normal. (If your battery is rated at 100 Ah, then C is 100, and C/20 is 5 A). Note how long it takes to get to that point, from when the voltage gets close to 29.0 V (if it gets there, of course).
Yes, you will presumably be in UTi output source priority (setting 01), which will ignore settings 12 and 13 (back to utility and back to battery voltage settings).
It probably doesn't matter much, but I would set this to about 0.15C for your battery, or another value if your battery manual specifies a different maximum charge current. The inverter will actually pay attention to this value, even though you can't reach it with utility charging; it uses this value to decide when to switch from absorb to float stages. [ Edit: At least, that's what the 5 kVA models do. 24 V models may operate differently. ] Exactly your problem, right? But increasing this value will make it switch to float sooner. But try the above experiment first. Let us know the result.

The main thing is not to end up with a clone, despite their lower price. Some clones might be OK, but you just don't know what you're getting, the the temptation to cut corners is always very high. Axpert quality is already so-so; I have replaced the capacitors and MOSFETs in mine (I have two, bought in 2015) to extend their life.
All the non-clones are basically made in the same factory to the same quality standard; there are a few odd brands that seem to get special treatment. Consider also that whoever you buy the machine from is probably the only place to get firmware updates, replacement comms boards, etc. You might be able to get firmware updates from a web site like this forum, but 24 V firmware update files are less common. You can sometimes get replacement boards from Ebay and the like, but it's almost impossible to be sure you're getting the exact right board (there are so many variations), and the quality is unknown.
 

Axpert 1000
DIY monitoring system based on Nodemcu/ESP8266-Emoncms( Local Win10-Apache).
Updated every 10 s.
PV producing 90 W
Battery differential + 47 W
Consumption ( Load ) 44  W
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